% kmeans聚类
%%
function [idx,C,k]=featureCluster(siftFeatures,k)
    featureNum=size(siftFeatures,1);
    % 采样减少样本的数量，要不太多了，跑了很久跑不出来 sampleGap=5;
    sampleGap=5;
    siftSample=siftFeatures(1:sampleGap:featureNum,:);
    [idx,C]=kmeans(siftSample,k);
end
